This beautiful “flower” could lead to better batteries and solar cells

Researchers at the University of North Carolina, in conjunction with the U.S. Army Research Office, crafted the beautiful design you see at the top out of germanium sulfide, which is a semi-conductor material. But they didn’t fabricate the nanoflower because it looked pretty. These beautiful real-life fractals could be the key to multiplying battery capacity and solar panel efficiency.

The researchers fabricaed the nanoflowers by heating germanium sulfide in a furnace until it vaporizes. Then, they blow the vapor to a colder part of the furnace, where it cools into thin sheets about 20-30 nanometers thick. They repeat the process and the sheets layer on top of each other until they look like a carnation or a marigold. The layers are the key to its technological potential: the more layers, the more surface area, which means greater capacity for an energy storage cell. Also, germanium sulfide’s atomic structure makes it very good at absorbing solar energy. More surface area means more places for light to hit and be absorbed. According to Linyou Cao, a co-author:

Creating these GeS nanoflowers is exciting because it gives us a huge surface area in a small amount of space. This could significantly increase the capacity of lithium-ion batteries, for instance, since the thinner structure with larger surface area can hold more lithium ions.

The press release from NC State can be found here, and the paper is available online in the journal ACS Nano.